The present invention relates to novel silicone emulsions. More particularly, the present invention relates to such silicone emulsions and polishes and treatments for fabrics, carpeting and draperies as well as cosmetics for hair and skin care and protective coatings made therefrom, wherein the polysiloxane employed in the emulsion is prepared by emulsion polymerization and wherein an ultraviolet light absorbing agent is added during such emulsion polymerization so that it is chemically bonded to the emulsion polymerized polysiloxane.
Silicone emulsion polishes are commonly used to improve the appearance of, as well as to protect, household products, luggage, marine and automobile vinyl and the like. While silicone emulsion polishes are generally regarded as excellent by those skilled in the art, they suffer from the shortcoming that when they are prepared by conventional mechanical methods the ultraviolet light absorbing agents contained therein are considered to be "fugitive" materials from the standpoint of various external conditions such as weathering, abrasion, heating and the like.
Silicone emulsions can also be diluted for use as a treatment for fabrics, upholstery, carpeting, draperies and the like. Treatment with such silicone emulsions imparts water and dirt repellency to the fabric as well as other advantageous properties.
It is known that silicone emulsions can advantageously be employed in many cosmetic applications such as hair conditioners, make-up, sun tanning lotions and the like.
In each of the foregoing applications, although protection against certain elements, for example, water and dirt, lasts for an extended period of time, protection against the sun's ultraviolet rays invariably is lost much sooner than desired. The present applicants have overcome such shortcoming by their discovery that extended protection against ultraviolet radiation can be obtained by chemically bonding an ultraviolet light absorbing agent directly onto polysiloxane polymers prepared by emulsion polymerization.
Those skilled in the art recognize that emulsions prepared by emulsion polymerization are characterized by extreme stability and extremely fine particle size. Moreover, those skilled in the art appreciate that the problems associated with preparing emulsions by emulsion polymerization are substantially different from those associated with preparing emulsions by mechanical means.
Hyde et al., U.S. Pat. No. 2,891,920, were the pioneers in the field of emulsion polymerization. Hyde et al. recognized that improved emulsions could be prepared by carrying out the polymerization of low molecular weight siloxanes while the siloxanes were dispersed in an aqueous media instead of emulsifying higher molecular weight siloxanes which were dissolved in an organic solvent. In carrying out the method of Hyde et al. the siloxane is first dispersed in the water, preferably with the use of an emulsifying agent, and a suitable polymerization catalyst is thereafter added to promote polymerization to the desired degree. Polymerization is carried out below the boiling point of water, although temperatures above 100.degree. C. can be employed if the polymerization is carried out in a closed system. Hyde et al. reveal that as the polymerization proceeds the viscosity of the siloxane increases but the size of the emulsion droplets decreases and it is believed that this is what causes the extremely stable emulsions obtained by emulsion polymerization.
Oppliger, U.S. Pat. No. 3,208,911, discloses a method for treating hair to improve the appearance, manageability and softness of the hair consisting essentially of submitting the hair to the action of an ionic oil-in-water emulsion, said emulsion being composed of an organosiloxane in an amount of from 0.01 to 90 percent by weight based upon the total weight of the emulsion and an ionic emulsifying agent in an amount of from 2 to 25 percent by weight based upon the weight of the organosiloxane and an alkaline catalyst in an amount of from one alkaline molecule per 100 silicon atoms to one alkaline molecule per 50,000 silicon atoms, inclusive, and the necessary water to give the desired solids content, said alkaline catalyst being selected from the group consisting of (a) R.sub.4 NOH and (b) R.sub.4 NX admixed with Q, wherein R is alkyl, X is an acid anion, and Q is an alkaline compound selected from the group consisting of ammonia, alkali metal hydroxides, alkali metal carbonates and organic amines, said ionic oil-in-water emulsion being prepared by polymerizing the organosiloxane in an aqueous medium in the presence of said alkaline catalyst until a viscosity of 6.5 cs. to 2.5.times.10.sup.6 cs. is obtained.
Findlay et al., U.S. Pat. No. 3,294,725, discloses an emulsion polymerization process similar to that of Hyde et al., however, Findlay et al. teaches the use of a surface active sulfonic acid as a polymerization catalyst rather than a strong mineral acid or strong alkali. A nonionic or anionic emulsifying agent can be employed if so desired.
Axon, U.S. Pat. No. 3,360,491, relates to emulsion polymerization of organosiloxanes wherein the polymerization catalyst is an organic sulfate of the general formula ROSO.sub.2 OH, wherein R is a monovalent aliphatic hydrocarbon radical of at least 6 carbon atoms. As is the case of Findlay et al., a nonionic or anionic emulsifying agent can be employed if so desired.
Cekada et al., U.S. Pat. No. 3,532,729, teaches the preparation of mercaptosiloxanes by emulsion polymerization.
Sorkin, U.S. Pat. No. 3,624,017, discloses an aqueous emulsion of a copolymer of 80 to 98 mole percent dimethylpolysiloxane and 2 to 20 mole percent RSiO.sub.3/2 in which R is methyl or vinyl, said emulsion having been prepared by emulsion polymerization of a mixture of dimethylpolysiloxane and RSiX.sub.3, in which X is a hydrolyzable group producing a water soluble by-product such as halogen,
--N(R.sup.1).sub.2 --ON.dbd.C(R.sup.1).sub.2, ##STR3## R.sup.1 C (.dbd.O)O--, R.sup.1 O(R.sup.2 O).sub.n -- and PA1 Q is --CH.sub.2 (CH.sub.2).sub.n Si(R.sup.2).sub.x (OR.sup.1).sub.y and W is --C.sub.m H.sub.2m+1, PA1 where x=0, 1 or 2, y=1, 2 or 3, x+y=3, PA1 R.sup.1 is an alkyl or alkanoyl radical having 1 to 6 carbon atoms, PA1 R.sup.2 is an alkyl radical having 1 to 6 carbon atoms, PA1 n=0, 1 or 2 and m=1 to 18.
--ON(R.sup.1).sub.2 in which R.sup.1 is a monovalent hydrocarbon or halocarbon radical and R.sup.2 is a divalent hydrocarbon or halohydrocarbon radical. It should be noted that the nitrogen-containing radicals of Sorkin are hydrolyzable and hence will not remain bonded to the siloxane chain in an aqueous medium.
Campbell, U.S. Pat. No. 3,634,297, provides a process for binding a pigment to glass fabric which comprises (A) applying to the glass fabric an aqueous emulsion of a copolymer consisting essentially of (a) 50 to 90 mole percent of (CH.sub.3).sub.2 SiO units and (b) 10 to 50 mole percent of RSiO.sub.3/2 units, wherein R is an alkyl or alkenyl radical of 1 to 3 carbon atoms, the 3,3,3-trifluoropropyl radical, or a phenyl radical, said copolymer having been prepared by emulsion polymerization; and a water dispersible pigment; and (B) drying the glass fabric.
Ikoma, U.S. Pat. No. 3,697,469, describes an emulsion polymerization process involving (i) emulsifying, in water containing a salt-type anionic surface active agent, an organosiloxane of the formula ##STR4## where R is a hydrogen atom or a monovalent hydrocarbon radical or a halogen substituted monovalent hydrocarbon radical, and a has an average value of 1 to 3, and then (ii) contacting said emulsion with an acid-type cationic exchange resin so that said surface active agent may be ion-exchanged from salt type into acid type, thereby acquiring catalytic power and at the same time starting the polymerization of said organosiloxane by making said emulsion an acid medium with a pH value of less than 4.
Backderf, U.S. Pat. No. 3,706,697, relates to aqueous emulsion polymerization of acryloxyalkyl-alkoxysilane, alkyl acrylic esters, and optionally other vinyl monomers to provide copolymers curable at low temperatures. The acryloxy functional site of the silane is said unexpectedly not to hydrolyze upon polymerization and thereby serve as a crosslinking site for reaction with the alkyl acrylic ester.
Hilliard, U.S. Pat. No. 3,898,300, describes an emulsion polymerization method to produce a polymeric styrene-acrylonitrile-polyorganosiloxane composition.
Huebner et al., U.S. Pat. No. 4,288,356, discloses a method of blending an emulsion of an emulsion polymerized compolymer of an organic monomer and an organosilicon monomer and an emulsion of a polydiorganosiloxane to provide a reinforced elastomeric product.
Traver et al., U.S. patent application Ser. No. 613,112, filed May 22, 1984, provides an aqueous emulsion prepared by emulsion polymerizing a diorganopolysiloxane in an aqueous medium in the presence of an emulsifier and thereafter stripping volatiles from the emulsion.
Simoneau et al., U.S. patent application Ser. No. 545,906, filed Oct. 27, 1983, describes aminofunctional silicone emulsions comprising an amino-terminated polydiorganosiloxane, an emulsifier and at least one member selected from the group consisting of (i) a polydimethylsiloxane oil or blend thereof having a viscosity ranging from 50 to 60,000 cps., (ii) an amount of glycerin effective to enhance the shelf stability of the emulsion, and (iii) an ultraviolet radiation absorbing compound of the type employed in the instant invention. A disadvantage of emulsions prepared in accordance with Simoneau et al. is that the emulsion is yellow in color and subsequently yields yellowish films.